W1209 Temperature Controller

The W1209 thermostat is a compact and versatile digital temperature controller designed for controlling heating or cooling systems based on temperature thresholds. It is widely used in DIY projects, aquariums, greenhouses, incubators, and various other temperature-sensitive environments.
Key Components: -Digital Display: A 3-digit 7-segment LED display shows the current temperature in real-time, as well as other key parameters during setup.
- Temperature Sensor: The W1209 typically comes with an NTC (Negative Temperature Coefficient) thermistor probe that measures the ambient temperature. The sensor has a range of -50°C to 110°C, with a typical accuracy of ±0.1°C.
- Control Buttons: There are three buttons (Set, +, -) on the board for configuring the temperature settings:
- Set Button: Used to enter the settings menu and confirm selections.
- Plus (+) Button: Increases the set temperature or adjusts parameters.
- Minus (-) Button: Decreases the set temperature or adjusts parameters.
Functional Features:
- Temperature Control: The W1209 can be set to either heating or cooling modes.
- In heating mode, the output is activated when the temperature falls below a set threshold.
- In cooling mode, the output is activated when the temperature exceeds a set threshold.
- Hysteresis Control: This feature prevents rapid cycling of the relay by allowing users to set a temperature range (difference between activation and deactivation). The relay will turn on or off based on this predefined difference.
- Relay Output: The W1209 is equipped with a relay (typically rated at 10A, 250V AC or 30V DC) that controls external devices (such as heaters or coolers). The relay is activated when the temperature crosses the set threshold, and deactivated when it returns to the target range.
- Calibration: Users can manually adjust the temperature reading to correct any discrepancies between the displayed and actual temperature.
- Delay Start: A delay timer can be set to prevent the relay from activating immediately after a power cycle, which helps protect connected devices from sudden power surges.
Power and Connections:
- Input Voltage: The board typically operates on a DC input voltage of 12V.
- Output Terminals: There are screw terminals for connecting the input power, connecting to the relay contacts, and an XH 2-pin header for the sensor connection.
User Interface:
- LED Indicators: The board has an LED indicator that shows when the relay is active.
- Configurable Settings: Users can easily set temperature limits, hysteresis, and delay through a simple button interface.
Dimensions:
50mm x 40mm x 15mm.
4 x 3.5mm mounting holes.